There was only one Maughold marriage between William Corkill & Catharine Kelly at that time, so all the children's bapts (last message) must have been from the same family, unless they married elsewhere and moved to Maughold, having children bapt at the same time.
1841 census Maughold, Ballagorrey Voar, Cottage:
William CORKILL 60 Ag lab Isle of Man
Cathrine CORKILL 60 Isle of Man [KELLY]
Cathrine CORKILL 30 Isle of Man bapt 19 Sep 1802
Mary LOONEY 14 Isle of Man(Mary Ann Illegitimate dau of George Looney & Mary Corkill bapt 1 Apr 1827).
Philip CRELLIN 10 Isle of Man (Philip, their grandson, son of Philip Crellen & Jane Corkill bapt 6 March 1830)
1841 census Ballagorry (3 19 79)
Mary CORKILL 35 Isle of Man
Margaret LOONEY 12 Isle of Man
Cathrine LOONEY 6 Isle of Man
1851 census Maughold Ballagorrey
William CORKILL head 70 Ag Lab b.Maughold
Catherine 75 wife b.Maughold
Catherine dau 47 Ag and Domestic b.Maughold
Margaret Looney granddau 22 ag and domestic (illeg.daur of Mary Ann Corkill & George Looney)
Sue